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South Atlantic tropical cyclone

From Academic Kids

A South Atlantic tropical cyclone is an unusual weather event which occurs below the equator in the southern Atlantic Ocean. Strong wind shear (which disrupts cyclone formation) and a lack of weather disturbances favorable for cyclone development make any hurricane-strength cyclones extremely rare.

Cyclone Catarina

Cyclone Catarina was an extraordinarily rare tropical cyclone, formed in the southern Atlantic Ocean in March, 2004. Just after becoming a hurricane, it hit the southern coast of Brazil near Laguna on the evening of March 28, with winds estimated near 135 km/h (85 mi/h), making it a category 1 storm. Catarina was compact, about 320 km (200 mi.) in diameter.

Brazilian meteorologists named the storm Catarina for its proximity to (and eventual landfall at) the state of Santa Catarina, although they have denied the storm, which clearly had an open eye, was a hurricane at all.

This event is considered by meteorologists to be a once-in-a-lifetime occurrence (though some believe climate change may make them more common). Catarina is one of only three South Atlantic cyclones to have been recorded by weather satellites, and the only one ever recorded to have reached hurricane-strength and to have hit land.

All names for this storm are "unofficial", in that no WMO-affiliated meteorological agency that monitors hurricanes named it. It has also been called "Aldonca", and the advisory names for it were "01T-ALPHA" from the United Kingdom's Met Office, and "01L-NONAME" from the National Hurricane Center.

The storm damaged over 30,000 homes, killed at least three and injured at least 38. [1] (http://www.usatoday.com/weather/news/2004-03-28-brazil-storm_x.htm)

Other South Atlantic Tropical Cyclones

In Mid-April of 1991, what may have been a tropical storm force cyclone was recorded by weather satellites off the coast of Angola. Additionally, on January 19, 2004, another cyclonic circulation developed just east of Salvador, Brazil. This storm was also believed to have been at tropical storm force and would mark the first time in recorded history that two tropical cyclones (Catarina and the January storm) have been seen during the same year in the South Atlantic.

On December 31, 2004, a weak tropical depression formed near N30.2 W47.5. Quickscats clearly showed a well-developed cyclone which had formed from a frontal low. The system later fell victim to high-level wind shear, as is common in the South Atlantic.